| [ Summary ] |
Gastroesophageal reflux was first evaluated in 1969 (more than 30 years ago) using esophageal pH monitoring. Esophageal pH monitoring was a useful technique to assess esophageal acid exposure in patients with erosive gastroesophageal reflux disease (GERD) with mucosal breaks in whom abnormal acid reflux is a common finding. However, in addition to the evaluation of acid reflux, it was necessary to evaluate non‒acid reflux to investigate the association between the onset of symptoms and reflux events in patients presenting with non‒erosive GERD who do not show mucosal breaks, as well as patients with proton pump inhibitor (PPI)‒resistant GERD. Esophageal impedance pH monitoring is a useful method to evaluate the properties (liquid, gas, mixture) of the contents of the reflux in addition to distinguishing between acid and non‒acid reflux. Esophageal impedance‒ pH monitoring is now utilized as the technique that provides the most conclusive evaluation of gastroesophageal reflux. |